| 摘要 |
PURPOSE:To obtain rigid polyurethane foam hardly restorable with the lapse of time even in groove processing by pressing processing, having excellent dimensional stability. CONSTITUTION:In producing rigid polyurethane foam by reacting a polyisocyanate component with a polyol component in the presence of a blowing agent and a catalyst, a polyol comprising (a) 35-50wt.% sucrose amine-based polyol having 400-600 hydroxyl number, (b) 30-45wt.% aromatic polyester polyol having 200-350 hydroxyl number and (c) 10wt.% or more ethylenediamine-based polyol having 700-800 hydroxyl number [with the proviso that (a)+(b)+C=100 wt.%] is used as the polyol component and the equivalent ratio of isocyanate group/hydroxyl group of 1.5-2.5 to produce rigid polyurethane. |
